Acer VG272 Lifecycle Extension Manual page 19

5.4 LED backlight debug flow：
LED driver Debug
Check Net
19V_BLD is
19V?
Y
BU1 is damaged?
N
BD1 is damaged?
N
N
Check BU2 pin5
is High
Y
Backlight on?
Y
END
Replace BL1
Y
N
BL1 is
open?
N
Y
Replace BU1
Y
Replace BD1
Open BR27
Check NET VB_CTRL
level is high?
Check U5 works
N
Reassemble BR67
Y
Y
N
Replace BU2
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